Chapters

Canna - Care Guide
Plants

Canna - Care Guide

Canna lily, Indian shot plant

One of the most striking groups of plants which are at their best at the Hampton Court Palace flower show in early July are cannas. The huge range of flower colours and leaf forms is impressive and certainly encourages visitors to try to acquire and grow these spectacular plants. However, one should not be carried away with excitement too quickly, as all these plants are half hardy or frost tender.

In cities throughout England cannas are incorporated into, and often the central feature of, summer bedding displays. The beds opposite Buckingham Palace are no exception. These plants are however overwintered indoors under glass and only planted out once the risk of frost subsides. Only in the most frost free coastal locations can they be risked outside all year round and, then, only in very rich soil conditions which have had leaf mould and dung added. Since these plants do have to grow on and flower so quickly they need a phosphate rich fertiliser once a month to push them on into growth and flowering. A thick autumn mulch will help protect those grown outside.

Many people will prefer to grow cannas in large pots which are put out onto the patio for the summer months. Otherwise the canna rhizomes should be dug and lifted before frosts threaten in the autumn. These rhizomes can be stored in trays or boxes with a covering of peat or leaf mould for protection in a frost free shed or garage. Before replanting in the spring clumps can be separated and the individual rhizomes cut into short sections with a prominent ‘eye’ shoot to create more plants. These offsets need to be grown on in pots for a year or two to reach flowering size.

The colourful and showy varieties which we offer include:

C. ‘Picasso’ which is a more compact growing variety (4ft) than many with yellow flowers spotted with reddish-brown.

C. ‘King Humbert’ grows to around 6ft with purple leaves and bright red flowers.

C. ‘Wyoming’ also grows to around 6ft with brown-purple leaves and orange flowers.

Other varieties are grown for their foliage effect as much as for their flowers:

C. ‘Striata’ achieves a height of around 5ft and has startling green leaves with bright yellow veining which contrasts well with its gladioli-like orange flowers.

C. ‘Tropicana Black’ has purple-black foliage and contrasting scarlet flowers fading to orange.

C. ‘Tropicana Gold’ has green leaves striped gold and yellow flowers edged with orange.